package com.lagou.edu.factory;

import com.lagou.edu.utils.Autowired;
import com.lagou.edu.utils.Service;
import com.lagou.edu.utils.TransactionManager;
import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

@Service
public class ProxyFactoryM {
    @Autowired
    private TransactionManager transactionManager;
    /**
     * JDK动态代理对象
     *
     */
    public Object getJDKProxy(Object obj){
        return Proxy.newProxyInstance(obj.getClass().getClassLoader(), obj.getClass().getInterfaces(), new InvocationHandler() {
            @Override
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                Object result=null;
                    try{
                        transactionManager.beginTransaction();//开启事务
                        result=method.invoke(obj,args);
                        transactionManager.commit();
                    }catch (Exception e){
                        e.printStackTrace();
                        transactionManager.rollback();
                        throw  e;
                    }
                return result;
            }
        });
    }
    /**
     * 使用cglib动态代理生成代理对象
     * @param obj 委托对象
     * @return
     */
    public Object getCglibProxy(Object obj) {
        return  Enhancer.create(obj.getClass(), new MethodInterceptor() {
            @Override
            public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
                Object result = null;
                try{
                    // 开启事务(关闭事务的自动提交)
                    transactionManager.beginTransaction();

                    result = method.invoke(obj,objects);

                    // 提交事务

                    transactionManager.commit();
                }catch (Exception e) {
                    e.printStackTrace();
                    // 回滚事务
                    transactionManager.rollback();

                    // 抛出异常便于上层servlet捕获
                    throw e;

                }
                return result;
            }
        });
    }

}
